Intracytoplasmic sperm injection (ICSI) in unexplained and stage I endometriosis-associated infertility after fertilization failure with in vitro fertilization (IVF)

Beyond the surface: Does stage I-II endometriosis impact fertility? Exploring the challenges of mild disease

Endometriosis is one of the most common gynecologic conditions that women face throughout their lives. Despite advances in technology, diagnosis and treatment of this relapsing and remitting condition is still challenging for many women. This review focuses on literature pertaining to minimal/mild (stage I/II) endometriosis and its impact on fertility. The effectiveness of medical interventions to improve infertility and obstetric outcomes in both natural and assisted reproductive technologies cycles remains debated. The recent ESHRE guidelines suggests that operative laparoscopy could be considered for rASRM stage I/II endometriosis as it improves ongoing pregnancy rates.

Efficacy of intracytoplasmic sperm injection in women with non-male factor infertility: A systematic review and meta-analysis

INTRODUCTION

The use of intracytoplasmic sperm injection (ICSI) has dramatically increased in patients with non-male factor infertility during the last decades. However, whether ICSI provides a significant benefit over in vitro fertilization (IVF) in these patients is still controversial. In this study, we aimed to investigate the efficacy of ICSI on reproductive outcomes with non-male factor infertility and to provide updated evidence for clinical practice.

MATERIAL AND METHODS

We searched Medline, Embase, and the Cochrane Central Register of Controlled Trials from inception to March 2023. Randomized controlled trials (RCTs) comparing the efficacy between ICSI and IVF in patients with non-male factor infertility were included. The main outcomes were the live birth rate (LBR), fertilization rate (FR), and total fertilization failure (TFF). The pooled estimates were calculated using the random-effects models as relative risk (RR) with 95% confidence intervals (CIs). This systematic review and meta-analysis was registered in PROSPERO (CRD42023427004).

RESULTS

We included 18 RCTs with 3249 cycles and 30 994 oocytes. The results demonstrated that ICSI reduced the risk of TFF (RR = 0.26, 95% CI: 0.13-0.50, I2  = 58%) and increased FR per oocyte inseminated/injected (RR = 1.14, 95% CI: 1.08-1.20, I2  = 69%), but it did not improve LBR (RR = 1.11, 95% CI: 0.94-1.30, I2  = 0%) or other outcomes compared with IVF. However, the difference in fertilization failure reduction between ICSI and IVF may be explained by different randomization methods (randomization based on patients vs. sibling oocytes). When considering only studies with randomization based on patients, we found no evidence of the difference between the groups (RR = 0.72, 95% CI: 0.48-1.06, I2  = 0%). Furthermore, no differences were observed in subgroup analyses based on other factors, including female age, study period, and controlled ovarian stimulation protocols.

CONCLUSIONS

Our findings suggest that ICSI leads to no difference in reproductive outcomes compared to IVF in patients with non-male factor infertility. Considering the cost and safety of ICSI, we have no evidence to support the routine use of ICSI in these populations. High-quality RCTs with large sample sizes will be needed to confirm our results and explore clinical and neonatal outcomes.

The definition of unexplained infertility: A systematic review

BACKGROUND

There is no consensus on tests required to either diagnose unexplained infertility or use for research inclusion criteria. This leads to heterogeneity and bias affecting meta-analysis and best practice advice.

OBJECTIVES

This systematic review analyses the variability of inclusion criteria applied to couples with unexplained infertility. We propose standardised criteria for use both in future research studies and clinical diagnosis.

SEARCH STRATEGY

CINAHL and MEDLINE online databases were searched up to November 2022 for all published studies recruiting couples with unexplained infertility, available in full text in the English language.

DATA COLLECTION AND ANALYSIS

Data were collected in an Excel spreadsheet. Results were analysed per category and methodology or reference range.

MAIN RESULTS

Of 375 relevant studies, only 258 defined their inclusion criteria. The most commonly applied inclusion criteria were semen analysis, tubal patency and assessment of ovulation in 220 (85%), 232 (90%), 205 (79.5%) respectively. Only 87/220 (39.5%) studies reporting semen analysis used the World Health Organization (WHO) limits. Tubal patency was accepted if bilateral in 145/232 (62.5%) and if unilateral in 24/232 (10.3%). Ovulation was assessed using mid-luteal serum progesterone in 115/205 (56.1%) and by a history of regular cycles in 87/205 (42.4%). Other criteria, including uterine cavity assessment and hormone profile, were applied in less than 50% of included studies.

CONCLUSIONS

This review highlights the heterogeneity among studied populations with unexplained infertility. Development and application of internationally accepted criteria will improve the quality of research and future clinical care.

Comparison of clinical outcomes between conventional in vitro fertilization and intracytoplasmic sperm injection in poor responders with only single oocyte retrieved

OBJECTIVE

To compare the clinical outcomes between conventional insemination (IVF) and intracytoplasmic sperm injection (ICSI) in poor responders with only a single oocyte retrieved.

MATERIALS AND METHODS

This is a retrospective case-control study. Couples who were treated with assisted reproductive technology (ART) with a single oocyte retrieved in Mackay Memorial Hospital from 1996 to 2016 were recruited. All data were categorized into three groups, according to their fertilization method and semen quality: group A, conventional insemination with non-male factor (IVF-NMF, n = 115), group B, ICSI with male factor (ICSI-MF, n = 30), and group C, ICSI with non-male factor (ICSI-NMF, n = 49).

RESULTS

No statistically significant difference was observed between IVF and ICSI groups in pregnancy outcomes, including the chemical or clinical pregnancy rate, miscarriage rate, and live birth rate. Similar fertilization rates per oocyte obtained were observed in IVF and ICSI patients, but significantly lower per mature oocyte in the ICSI group (IVF: 91.5%, ICSI-MF: 75.0%, ICSI-NMF: 77.8%). Although there is no statistical significance, the lower live birth rate is observed in group C than others (A:11.5%, B:25%, C:5%, p = 0.187).

CONCLUSION

In this study, pregnancy outcomes of conventional in vitro fertilization and ICSI in poor responders with only a single oocyte retrieved were similar. However, the fertilization rate of matured oocytes in ICSI groups is significantly lower than that in the IVF group, indicating that ICSI procedures might cause oocyte damage. Therefore, the choice of fertilization method should be based on semen quality. A randomized controlled trial should be performed to confirm our findings.

The effect of ICSI in infertility couples with non-male factor: a systematic review and meta-analysis

PURPOSE

We performed a systematic review and meta-analysis of available literature to investigate the efficacy of the intracytoplasmic sperm injection (ICSI) in couples with non-male factor with respect to the clinical outcomes.

METHODS

The literature search was based on EMBASE, PubMed, and the Cochrane Library. All studies published after 1992 until February 2020 and written in English addressing patients in the presence of normal semen parameters subjected to ICSI and in vitro fertilization (IVF) were eligible. Reference lists of retrieved articles were hand-searched for additional studies. The primary outcomes were fertilization rate, clinical pregnancy rate, and implantation rate; the secondary outcomes were good-quality embryo rate, miscarriage rate, and live birth rate.

RESULTS

Four RCTs and twenty-two cohort studies fulfilling the inclusion criteria were included. Collectively, a meta-analysis of the outcomes in RCTs showed that compared to IVF, ICSI has no obvious advantage in fertilization rate (RR = 1.16, 95% CI: 0.83-1.62), clinical pregnancy rate (RR = 1.04, 95% CI: 0.66-1.64), implantation rate (RR = 1.12, 95% CI: 0.67-1.86), and live birth rate (RR = 1.17, 95% CI: 0.43-3.15). Pooled results of cohort studies demonstrated a statistically significant higher fertilization rate (RR = 1.16, 95% CI: 1.03-1.31) and miscarriage rate (RR = 1.04, 95% CI: 1.01-1.06) in the ICSI group; furthermore, higher clinical pregnancy rate (RR = 0.85, 95% CI: 0.77-0.94), implantation rate (RR = 0.78, 95% CI: 0.65-0.95), and live birth rate (RR = 0.86, 95% CI: 0.79-0.94) was founded in the IVF group; no statistically significant difference was observed in good-quality embryo rate (RR = 0.98, 95% CI: 0.93-1.04).

CONCLUSION

ICSI has no obvious advantage in patients with normal semen parameters. Enough information is still not available to prove the efficacy of ICSI in couples with non-male factor infertility comparing to IVF.

Impaired implantation in endometriosis compared with couples with male subfertility after transfer of equal quality embryos: a matched cohort study

RESEARCH QUESTION

Is implantation impaired in patients with endometriosis undergoing IVF and intracytoplasmatic sperm injection (ICSI) cycles?

DESIGN

A retrospective matched cohort study was carried out on IVF/ICSI cycles with fresh single embryo transfer at the Department of Assisted Reproductive Medicine, Ghent University Hospital, Belgium, between July 2015 and August 2017 (n = 1053). A total of 118 endometriosis cases were matched 1:1 to 118 couples diagnosed with male subfertility and stratified by embryo quality (identical ALPHA grading categories), female age (±1 year) and parity (±1 delivery). Transvaginal ultrasound, magnetic resonance imaging or laparoscopy was used to diagnosed endometriosis, and the revised American Society for Reproductive Medicine score was used to classify the endometriosis into grade I/II versus grade III/IV. Male subfertility was defined in accordance with World Health Organization criteria (fifth edition).

RESULTS

Compared with endometriosis cases, control couples with male subfertility had significantly higher rates of positive HCG test on day 16 (P = 0.047, OR 2.077, CI 1.009 to 4.276), ongoing implantation (defined as a positive fetal heart rate on transvaginal ultrasound at a gestational age of at least 6.5-7 weeks) (P = 0.038, OR 2.265, CI 1.048 to 4.893), ongoing pregnancy (defined by a vital pregnancy at 11 weeks) (P = 0.046, OR 2.292, CI 1.016 to 5.173) and live birth (P = 0.043, OR 2.502, CI 1.029 to 6.087).

CONCLUSIONS

After matching for embryo quality, woman's age and parity, rates of positive HCG tests, ongoing implantation, ongoing pregnancy and live birth were more than twice as high in the control group compared with the endometriosis group.

Reproductive, obstetric, and perinatal outcomes of women with adenomyosis and endometriosis: a systematic review and meta-analysis

BACKGROUND

The reproductive impact of adenomyosis and endometriosis is widely researched but the extent of these impacts remains elusive. It has been demonstrated that endometriosis, in particular, is known to result in subfertility but endometriosis and adenomyosis are increasingly linked to late pregnancy complications such as those caused by placental insufficiency. At the molecular level, the presence of ectopic endometrium perturbs the endometrial hormonal, cellular, and immunological milieu, negatively influencing decidualization, placentation, and developmental programming of the embryo. It is unclear if and how such early aberrant reproductive development relates to pregnancy outcomes in endometriosis and adenomyosis.

OBJECTIVE AND RATIONALE

The aims of this systematic review and meta-analysis were to (i) investigate the association of adenomyosis and endometriosis with fertility, obstetric, and neonatal outcomes of women through both assisted reproduction and natural conception and (ii) determine whether endometriosis disease subtypes have specific impacts on different stages of the reproductive process.

SEARCH METHODS

A systematic literature review of NHS evidence electronic databases and the Cochrane database identified all comparative and observational studies between 1980 and December 2018 in any language on adenomyosis and endometriosis with fertility, obstetric, and neonatal outcomes (23 search terms used). A total of 104 papers were selected for data extraction and meta-analysis, with use of Downs and Black standardized checklist to evaluate quality and bias.

OUTCOMES

We found that endometriosis consistently leads to reduced oocyte yield and a reduced fertilization rate (FR), in line with current evidence. Milder forms of endometriosis were most likely to affect the fertilization (FR OR 0.77, CI 0.63-0.93) and earlier implantation processes (implantation rate OR 0.76, CI 0.62-0.93). The more severe disease by American Society for Reproductive Medicine staging (ASRM III and IV) influenced all stages of reproduction. Ovarian endometriosis negatively affects the oocyte yield (MD -1.22, CI -1.96, -0.49) and number of mature oocytes (MD -2.24, CI -3.4, -1.09). We found an increased risk of miscarriage in both adenomyosis and endometriosis (OR 3.40, CI 1.41-8.65 and OR 1.30, CI 1.25-1.35, respectively), and endometriosis can be associated with a range of obstetric and fetal complications including preterm delivery (OR 1.38, CI 1.01-1.89), caesarean section delivery (OR 1.98 CI 1.64-2.38), and neonatal unit admission following delivery (OR 1.29, CI 1.07-1.55).

WIDER IMPLICATIONS

Adenomyosis and the subtypes of endometriosis may have specific complication profiles though further evidence is needed to be able to draw conclusions. Several known pregnancy complications are likely to be associated with these conditions. The complications are possibly caused by dysfunctional uterine changes leading to implantation and placentation issues and therefore could potentially have far-reaching consequences as suggested by Barker's hypothesis. Our findings would suggest that women with these conditions should ideally receive pre-natal counselling and should be considered higher risk in pregnancy and at delivery, until evidence to the contrary is available. In order to expand our knowledge of these conditions and better advise on future management of these patients in reproductive and maternal medicine, a more unified approach to studying fertility and reproductive outcomes with longer term follow-up of the offspring and attention to the subtype of disease is necessary.

Live birth rates using conventional in vitro fertilization compared to intracytoplasmic sperm injection in Bologna poor responders with a single oocyte retrieved

PURPOSE

To compare reproductive outcomes following conventional in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) in poor responders fulfilling the Bologna criteria, with a single oocyte retrieved.

METHODS

The present retrospective study included 243 Bologna poor responders with a single oocyte retrieved, who were categorized into three groups, depending on the fertilization method and semen quality (IVF non-male factor-IVF/NMF n = 101; ICSI non-male factor ICSI/NMF n = 50; ICSI male factor-ICSI/MF n = 92).

RESULTS

In IVF/NMF, ICSI/NMF and ICSI/MF similar fertilization rates [65.3, 66, 58.7%, respectively], proportions of embryo formation [63.4, 60, 53.3%, respectively], proportions of good quality embryos [54.7, 56.7, 57.1%, respectively], implantation rates [8.9, 10, 8.2% respectively] and live birth rates per oocyte retrieval [5.0, 4.0, 3.3%, respectively] were observed. Degeneration rate of oocytes due to mechanical damage was significantly higher after ICSI in the ICSI/NMF and ICSI/MF groups (8 and 6.5%, respectively) compared to IVF/NMF (0%) (p = 0.02).

CONCLUSIONS

Conventional IVF and ICSI are associated with similar reproductive outcomes in poor responder patients with a single oocyte retrieved. Therefore, the choice of fertilization method should be based primarily on semen quality, in combination with the patient's previous history. A randomized controlled trial should be performed to confirm this study's findings that conventional IVF and ICSI have similar reproductive outcomes in poor responders.

Impact of endometriosis and its staging on assisted reproduction outcome: systematic review and meta-analysis

OBJECTIVE

To evaluate whether the presence or severity of endometriosis affects the outcome of assisted reproductive techniques (ART).

METHODS

In this systematic review, all studies comparing the outcome of ART in women with and those without endometriosis, or at different stages of the disease, were considered eligible. We used either risk ratio (RR) or mean difference (MD) and their 95%CIs for comparisons. The primary outcome was live birth; the secondary outcome was clinical pregnancy. Miscarriage and the number of oocytes retrieved were examined as additional outcomes.

RESULTS

We included 92 studies in the review and 78 in the meta-analysis: 20,167 women with endometriosis were compared with 121,931 women without endometriosis, and 1703 women with Stage-III/IV endometriosis were compared with 2227 women with Stage-I/II endometriosis. The following results were observed for the comparison of women with endometriosis vs women without endometriosis: live birth, RR = 0.99 (95%CI, 0.92-1.06); clinical pregnancy, RR = 0.95 (95%CI, 0.89-1.02); miscarriage, RR = 1.31 (95%CI, 1.07-1.59); number of oocytes retrieved, MD = -1.56 (95%CI, -2.05 to -1.08). The following results were observed for the comparison of women with Stage-III/IV vs Stage-I/II endometriosis: live birth, RR = 0.94 (95%CI, 0.80-1.11); clinical pregnancy, RR = 0.90 (95%CI, 0.82-1.00); miscarriage, RR = 0.99 (95%CI, 0.73-1.36); number of oocytes retrieved, MD = -1.03 (95%CI, -1.67 to -0.39).

CONCLUSIONS

Women with endometriosis undergoing ART have practically the same chance of achieving clinical pregnancy and live birth as do women with other causes of infertility. No relevant difference was observed in the chance of achieving clinical pregnancy and live birth following ART when comparing Stage-III/IV with Stage-I/II endometriosis. The quality of the evidence for the additional examined outcomes was very low, not allowing meaningful conclusions to be drawn.

Peri-implantation hormonal milieu: elucidating mechanisms of abnormal placentation and fetal growth

Assisted reproductive technologies (ART) have been associated with several adverse perinatal outcomes involving placentation and fetal growth. It is critical to examine each intervention individually in order to assess its relationship to the described adverse perinatal outcomes. One intervention ubiquitously used in ART is superovulation with gonadotropins. Superovulation results in significant changes in the hormonal milieu, which persist during the peri-implantation and early placentation periods. Epidemiologic evidence suggests that the treatment-induced peri-implantation maternal environment plays a critical role in perinatal outcomes. In this study, using the mouse model, we have isolated the exposure to the peri-implantation period, and we examine the effect of superovulation on placentation and fetal growth. We report that the nonphysiologic peri-implantation maternal hormonal environment resulting from gonadotropin stimulation appears to have a direct effect on fetal growth, trophoblast differentiation, and gene expression. This appears to be mediated, at least in part, through trophoblast expansion and invasion. Although the specific molecular and cellular mechanism(s) leading to these observations remain to be elucidated, identifying this modifiable risk factor will not only allow us to improve perinatal outcomes with ART, but help us understand the pathophysiology contributing to these outcomes.

The effect of endometriosis on in vitro fertilisation outcome: a systematic review and meta-analysis

BACKGROUND

Endometriosis is found in 0.5-5% of fertile women and 25-40% of infertile women. It is known that endometriosis is associated with infertility, but there is uncertainty whether women with endometriosis have adverse pregnancy outcomes in in vitro fertilisation (IVF) treatment.

OBJECTIVES

To explore the association between endometriosis and IVF outcome.

SEARCH STRATEGY

Searches were conducted on MEDLINE, EMBASE, Cochrane Library and Web of Science (inception, December 2012) in all languages, together with reference lists of retrieved papers.

SELECTION CRITERIA

Studies comparing IVF outcome in women with endometriosis with women without endometriosis. Patients were classified by stage of endometriosis. The outcomes were fertilisation, implantation, clinical pregnancy and live birth rates. Study selection was conducted independently by two reviewers. The Newcastle-Ottawa Quality Assessment Scale was used for quality assessment.

DATA COLLECTION AND ANALYSIS

Data extraction was conducted independently by two reviewers. Relative risks from individual studies were meta-analysed.

MAIN RESULTS

Twenty-seven observational studies were included, comprising 8984 women. Meta-analysis of these studies showed that fertilisation rates were reduced in stage I/II of endometriosis (relative risk [RR] = 0.93, 95% confidence interval [95% CI] 0.87-0.99, P = 0.03). There was a decrease in the implantation rate (RR = 0.79, 95% CI 0.67-0.93, P = 0.006) and clinical pregnancy rate (RR = 0.79, 95% CI 0.69-0.91, P = 0.0008) in women with stage III/IV endometriosis undergoing IVF treatment.

CONCLUSION

The presence of severe endometriosis (stage III/IV) is associated with poor implantation and clinical pregnancy rates in women undergoing IVF treatment.

In vitro fertilization is a successful treatment in endometriosis-associated infertility

OBJECTIVE

To assess success rates of IVF and intracytoplasmic sperm injection in women with various stages of endometriosis.

DESIGN

Retrospective cohort study.

SETTING

Reproductive medicine unit in a university hospital.

PATIENT(S)

Infertile women (n = 2,245) with various stages of endometriosis or tubal factor infertility.

INTERVENTION(S)

IVF or intracytoplasmic sperm injection.

MAIN OUTCOME MEASURE(S)

Dose of FSH, number of oocytes retrieved, fertilization rate, implantation rate, pregnancy rate (PR), live birth/ongoing PR.

RESULT(S)

Women with endometriosis had similar pregnancy and live birth/ongoing PR as did women with tubal factor infertility, but the American Society for Reproductive Medicine (ASRM) stage I and II endometriosis patients had a lower fertilization rate, and stage III and IV patients required more FSH and had fewer oocytes retrieved. Splitting the stage III and IV groups into patients with and without endometriomas showed that the endometrioma group required more FSH and had a significantly lower pregnancy and live birth/ongoing PR.

CONCLUSION(S)

With the exception of patients with endometrioma, infertile women with various stages of endometriosis have the same success rates with IVF and intracytoplasmic sperm injection as patients with tubal factor. This contrasts with the systematic review on which the European Society of Human Reproduction and Embryology bases its recommendations.

Fertility in women with minimal endometriosis compared with normal women was assessed by means of a donor insemination program in unstimulated cycles

OBJECTIVE

The purpose of this study was to compare the pregnancy rate in an artificial insemination donor program in women with minimal endometriosis and in women without endometriosis.

STUDY DESIGN

A prospective double-blinded study was conducted in women with azoospermic partners.

RESULTS

The per-cycle pregnancy rate was 8.6% (9/104 women) in the minimal endometriosis group vs 13.3% (26/196 women) in the control group. The per-woman pregnancy rate was 37.5% (9/24 women) in the minimal endometriosis group and 51.0% (26/51 women) in the control group.

CONCLUSION

Pregnancy rates were statistically similar in normal women and in women with minimal endometriosis.

[Which technique is best for which male infertility?]

To what extent are sperm analyses valid? Does a normality benchmark exist? Analysis of the literature suggests that the normal values for semen parameters defined by the WHO may require reassessment. Other criteria should perhaps be taken into account, such as chromatin or DNA abnormalities. The existing studies are contradictory and the DNA fragmentation rate is not used by the ASRM as a predictor of the pregnancy rate. Several teams have attempted to suggest threshold values for semen parameters, both in cases of intrauterine insemination and ICSI. In the case of IUI, the results are highly variable depending on the study in question. As for ICSI, although there is some consensus of opinion in the data, other findings are controversial or debatable. However, there are few properly conducted randomised prospective studies and very few multivariate analyses.